1. Field of the Invention
The present invention relates to a substrate board. More particularly, the present invention relates to a flexible substrate board, a fabrication method thereof and a display using the same.
2. Description of Related Art
For a flexible electronic product or a flexible display, components such as electronic components with stable characteristics therein are indispensable. However, regardless of fabricating by a high-extensive or a low-ductility material, after the electronic device is elongated for a long time, it can be cracked due to an elastic fatigue thereof. Such phenomenon is a great problem for applications of the flexible electronic product and the flexible display.
Presently, a solution of the above problem is based on a material substitution method. For example, a material with high ductility is applied to the electronic device to slow down a shifting of the characteristic of the electronic device during the elongation process. According to the above material substitution method, a silicon material is, for example, substituted by an organic semiconductor, silicon oxide or silicon nitride is substituted by an organic insulation layer, and a vacuum thin-film process is substituted by a metal solution process, etc. However, the characteristic of the electronic device is still slowly changed during the elongation process and cannot be stable, so that a solution thereof is still required.
A U.S. Patent No. 2006/0204675 discloses a method to implement a rigid area and a flexible area by combining different materials. Referring to FIG. 1A, FIG. 1A is a cross-sectional view of a flexible substrate board fabricated according to the U.S. Patent No. 2006/0204675. The substrate board 100 is composed of different materials, and includes a rigid area 110 composed by a rigid material and a flexible area 120 composed by a flexible material, wherein a pixel 130 is disposed on the rigid area 110. Such substrate is fabricated by using a coextrusion roller. FIG. 1B is a schematic diagram of the coextrusion roller. First, a manifold 140 provides a multi-section layer 150 having the rigid area 110 and the flexible area 120 shown in FIG. 1A. The multi-section layer 150 is extruded by rollers 160, 162 and 164 and is combined to a substrate 170 having the pixel 130 or other circuit devices to form the aforementioned flexible substrate board. According to such method, the flexible characteristic of the substrate board can be achieved base on a difference of the material characteristics. However, during the extrusion process, the devices on the substrate 170 have to be accurately aligned to the rigid area 110 or the flexible area 120 with totally different characteristics, which may lead to a great difficulty for the fabrication process. Therefore, the method is not widely applied.
Moreover, a U.S. Patent No. 2008/0002118 and a U.S. Patent No. 2008/0053604 respectively disclose a flexible substrate board, in which a substrate and a flexible substrate are combined according to a gluing method, so as to achieve the flexibility.
In addition, a U.S. Patent No. 2005/0259189, a U.S. Patent No. 2007/0052670, a U.S. Patent No. 2006/0132025 and a U.S. Pat. No. 6,710,841 respectively disclose a flexible substrate board, in which the flexibility is achieved based on the difference of the material characteristics or a difference of thickness of a plurality of substrates.
In the aforementioned related techniques, different materials with different characteristics are applied to achieve the flexibility of the substrate board, which all have difficulties and problems in application.